(KMOV.com) – The Ferguson-Florissant School District is investigating a fight outside of McCluer North High School Tuesday that involved at least a dozen students.

A video of the fight was posted online.

The district says about 12 students were involved and officials are investigating whether a 13th also took part in the fight.

It broke out outside the high school during dismissal right where the buses line up to take students home.

Police report it started with two students hitting a third, then others got off buses and joined in.

The 20 second video appears to be taken from inside a bus.

In it, someone can be heard shouting, “Open the doors!”Then a woman off-camera can be heard saying, “She’s not authorized to do that.”

“Obviously the fight was occurring outside of the school bus,” said Janna Shorrt with the district. “And to open that door would have potentially put students that were on the bus in danger. And so, the driver let them know that the doors would not be opened in that situation.”

There is a student resource officer assigned to McCluer North. That officer was on scene and called for backup.

Two students were taken into custody.

The district says that the students involved in the fight were suspended.

Their parents will be asked to attend a disciplinary hearing and the school will then decide if more action would be taken.